The objectives of the proposed research are as follows: 1. To isolate sufficient quantity of Beta-lipotropin from human pituitary glands for biological and chemical studies. To elucidate the complete amino acid sequences of human Beta-LPH and compare its primary structure with the hormone from other species. 2. To continue the synthesis of ACTH and MSH peptides with the following aims: (a) to further define those structure features of the hormone which are essential for the biological functions; (b) to prepare peptides which are long-acting as well as peptides which can be administered orally; (c) to prepare peptides which inhibit biological activity of the hormone. 3. To investigate the mode of action of ACTH and MSH on the adrenal gland and adipose tissue by the following approaches: (a) localization of ACTH in the adrenal gland; (b) isolation of binding sites (receptors) of ACTH in the rat cells as well as the rat fat cells and of MSH in rabbit fat cells; (c) investigation of action of ACTH and MSH in terms of biochemical parameters (stimulation of adenyl cyclase, prostaglandin levels, etc.) in the adrenal and adipose tissues of different species.